can't boot with kern.mmxopt=1

Richard Nyberg rnyberg at it.su.se
Tue May 4 09:59:14 PDT 2004


At Tue, 4 May 2004 09:09:49 -0700 (PDT),
Matthew Dillon wrote:
> 
> :Anyway, hopefully it works and I don't have to dance with DDB.
> :

Now I've tried the first patch too, but it stops in the same place,
and I can't break to the debugger :(

>     Maybe it's related to the HTT (hyper threading technology).  What happens 
>     if you do a UP build on that machine instead of SMP ?
> 

Ok I can try make a UP build, but...

This machine is a little peculiar when it comes to HTT. Most often the
second CPU reports its highest id to the mptable which makes the "find
logical cpus" hack in dragonfly bail out. This means I almost always only
run proper SMP.

BTW, I think freebsd current enumrates the cpu via acpi instead of mptable.
Is this planned for dragonfly?

Happy hacking!
	-Richard





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